I will always love Jon Irenicus by David Warner. When I was young playing BG2 as non English speaker for the first time that crisp and sharp English pronunciation stuck in my head as I was able to understand it clearly. That voice is perfect fit for the character of Jon too.
Later I was surprised I saw David in one of Terry Pratchett 's movie Hogfather as Lord Downey - there was something behind his voice familiar to me but I could not put my finger on it - later when he died I read one article where both voice acting for Irenicus and his role in Hogfather was mentioned.... aaaand it finally clicked in my head ..that strange feeling of realization :) I love BG and Pratchett's books and movies very much.